Drill.



if. Q\ W a Patented July 22, 1913.

" 0 M. TILSON.

DRILL.

APPLIOATION FILED JULY 20, 1912.

UNTTED @TATE% CHARLES M. TILSON, 0F WILKES-BARRE, PENNSYLVANIA.

DRILL.

inseam.

Specification of Letters Patent.

Application filed July 20, 1912.

Patented July as, rare. Serial No. 710,628.

To all whom it may concern Be it known that 1, CHARLES M. TILsoN, acitizen of the United States, residing at Wilkes-Barre, in the county ofLuzerne and State of Pennsylvania, have invented new and usefulImprovements in Drills, of which the following is a specification.

This invention relates to improvements in drills, especially drills formining coal, the object of the invention being to provide an in'iproveddrill of this kind which has a removable and reversible center bit andis also provided with a radially adjustable side or reaming bit whichmay be set to drill an opening of any desired diameter, the inventionconsisting in the construction, combination and arrangement of devices,hereinafter described and claimed.

In the accompanying drawings:Figure 1 is an elevation of a coal drillconstructed in accordance with my invention, with a portion of the shankor socket in section. Fig. 2 is a plan of the same. Fig. 3 is asectional view of the same on the plane indicated by the line aa ofFig. 1. Fig. 4 is a detail perspective view of the center bit. Fig. 5 isa similar view of the side or reaming bit. Fig. 6 is a detailperspective view of the center bit, showing the opposite side thereoffrom that shown in Fig. 4.

The shank l of my improved drill comprises the usual cylindrical portion2 and a spiral flight 3. The shank has a cross sectionally rectangularsocket 1 which is open at the outer end of the shank and at the innerend of the said socket is a shoulder 5. The outer end of the shank isprovided at one side with a radially projecting portion 6. An inclinedcross sectionally rectangular socket 7 is made in the shank, the outerend of the said socket 7 passing through the projection 6 and the innerend of the said socket being at one side of the shank and spaced fromthe outer end thereof, as indicated at 8. This socket 7 intersects oneside of the socket 4. The transverse opening 9 is made through the shanknear its outer end and intersects one corner of the socket at, a splitcotter pin 10 being provided which is adapted to be placed in the saidopening.

In connection with the shank or socketed portion of my improved drill, Iprovide a center bit or cutter 11 and a side bit or reamer 12. Thecenter bit 11 is shown as provided at its outer end with divergingcutter points or arms 13. The stalk or body of the center bit is crosssectionally rectangular, is of a size and shape adapting it to fit inthe socket 4 of the shank 1 and at the inner end of the said center bitis a recess 14 which provides a shoulder 15 that is adapted to abutagainst the shoulder 5 of the socket 4 when the center bit is so placedin the socket as to reach the bottom thereof. In one side of the centerbit, that being the side opposite that in which the recess 14 isprovided is a transverse inclined recess 16 which, when the bit 11 is inplace in the socket 4 is coincident with the socket 7 so that when theside or reaming bit 12 is placed in the inclined socket 7 it passesthrough the recess 16 of the center bit 11.

The recessed face of the center bit is provided with longitudinalratchet teeth 17. The opposite side of the center bit is provided withsimilar ratchet teeth 18 which extend to the shoulder 15. The side orream ing bit 12 is provided on one side with a series of ratchet teeth19 which are oblique thereto and at such an angle that when the saidside or reaming bit is in place in the inclined socket 7 its teeth 19are exactly parallel with the longitudinal teeth 17 or 18, as the casemay be, of the center bit 11 so that the said teeth 19 of the side orreaming bit may engage teeth 17 or 18 of the center bit. This admits ofthe longitudinal adjustment of the side or reaming bit so that its outerend may be extended to any desired distance radially from the shank ofthe drill according to the desired diameter of the hole or bore to becut by the drill, when operating in the coal. The center bit is held inplace by the split cotter pin 10, the said pin passing through one of apair of diagonally opposite notches 20-21 with which the shank of thecenter bit is provided at diagonally opposite corners.

hen the center bit is fully in place in the socket at, the side orreaming bit engages the teeth 17. After the center bit has been worn,however, it may be readjusted so as to project its outer end furtherfrom the outer end of the shank l and when thus readjusting the centerbit, it must be turned partly around and disposed in reverse relation inthe socket 4 with the inner end of the center bit engaged with theshoulder 5.

While I have herein shown and described a preferred form of myinvention, I would have it understood that changes may be made in theform, proportion and construca shank having a longitudinal socket and astop in said socket, said shank also having an inclined socket at oneend of and partly intersecting the longitudinal socket, in combinationwith a center bit having longitudinal teeth in opposite sides spaced atdifferent distances from its inner end and also having recesses at theinner ends of the teeth, one of said recesses extending to the inner endof the said bit and forming a shoulder to bear against the stop when thesaid bit is in one position, the inner end of said bit bearing againstthe stop When said bit is in another position, and a side or reaming bitto fit in the inclined socket and having teeth on one side to engageeither series of teeth of the center bit according to the adjustment ofthe latter.

In testimony whereof I affix my signature in presence of two Witnesses.

CHARLES M. TIL SON.

Vitnesses:

W. C. GREGORY, H. L. GREGORY Copies of this patent may be obtained forfive cents each, by addressing the Commissioner of Patents. Washington,D. C.

